deleteLinesAtSelections method

Implementation

bool deleteLinesAtSelections() {
  return _runEditFrame(() {
    _beginHistoryAction(
      _TextAreaHistoryAction.deleteForward,
      breakChain: true,
    );
    _refreshDocumentSnapshot();
    final lines = _selectedLineIndexes().toList()
      ..sort((a, b) => b.compareTo(a));
    if (lines.isEmpty) return false;
    final graphemes = _document.flattenWithNewlines();
    var next = selections;
    var changed = false;
    for (final line in lines) {
      final start = _document.lineStartOffset(line);
      final end = _document.lineEndOffset(line, includeTrailingNewline: true);
      if (start == end) continue;
      if (!changed) _recordUndoSnapshot();
      graphemes.replaceRange(start, end, const <String>[]);
      next = next.applyDeletion(startOffset: start, endOffset: end);
      changed = true;
    }
    if (!changed) return false;
    _replaceText(graphemes.isEmpty ? '' : graphemes.join());
    setSelections(next);
    return true;
  });
}